I will be using the following equipment:
Bunsen burner
Latex Gloves
Paper
Hole-punch
Polythene rod
Cloth
Rulers
Hair dryer
Top pan balance
Fair Test
I will need to keep my experiment a fair test so that I can be sure my results are accurate. I will only be changing the amount of rubs however I will pay particular attention to some things that it is vital to keep the same. I will keep all stages of the experiment under the same conditions by using a hair dryer. I will also not change any of the equipment because some items may work better than others. Another thing I will be doing is wearing latex gloves so that any moisture from my hands will not affect my experiment. One of the most important things I must do is to ensure there is no charge remaining on the rod when I proceed to the next stage of my experiment so I will monitor this very closely.
Hypothesis
I think that the more rubs I do on my rod the greater the number of paper circles I will pick up. This is because every time I rub my rod with the cloth it is stripping electrons off the atoms in the cloth and creating a negatively charged rod. When I then move my cloth over the paper circles it creates an induced positive charge at the top of the paper. This is when the electrons are pushed towards the bottom of the paper because of the repelling electrons in the rod. Thus meaning there is more protons than electrons at the top of the paper. Therefore the top of the paper is attracted to the rod and the paper jumps to the rod. This is because the two opposing forces attract and come together.
Preliminary results
I did these preliminary results but only needed to do one group because I immediately realised what the problem was.
From this I discovered that the paper was getting charged so I placed all the paper in a metal dish and then placed them on a radiator to allow the charge to flow to earth. Following this my results worked well.
Results
For the weight of paper picked up I had to do the following sum.
Weight of 250 paper circles / 250 = weight of 1 paper circle
Weight of 250 paper circles / 250 = 0.00028
Analysis
My results show a trend that proves my hypothesis wrong. This is that the more rubs I do the more paper circles I pick up. I think that my hypothesis was the correct one to male and that I made my experiment a fair test in a good way. I think that my experiment worked well because every time I rubbed my rod with the cloth it stripped electrons off the atoms in the cloth and thus it created a negatively charged rod. When I then moved my cloth over the paper circles it created an induced positive charge at the top of the paper. This is when the electrons are pushed towards the bottom of the paper because of the repelling electrons in the rod. Thus meaning there is more protons than electrons at the top of the paper. Therefore the top of the paper is attracted to the rod and the paper jumps to the rod. This is because the two opposing forces attract and come together.
Conclusion
In my opinion my experiment worked perfectly I got a clear trend in my results and found no anomalies. I think it worked so well because I went to great lengths to ensure no charge contamination occurred. I took precautions such as discharging the paper, wearing latex gloves and using a hairdryer. I used the hair dryer and gloves to ensure no charge was lost through moisture in the air and I discharged the paper so that no charge acted with or against the charge on the rod.
If I was to carry out this experiment again I would cut out 3750 paper circles and then take an average weight of this and use new paper for each set of results. This way I would ensure that the paper did not gain a charge of its own and thus affected the charge of the rod when picking up paper. This effect could have easily ruined my experiment however I found a way to discharge my paper on a radiator.
I have researched electrostatics and found another way to complete this experiment and gain the same results. I would use a gold leaf electroscope. This would show me an angle of which a charge induced. For example where my results go up in weight the results would go up with an angle. This would ultimately show the same trend if both experiments were carried out correctly.
